Generally,high performance thermoelectric materials should have both low thermal conductivity and high power factor.Current state-of-the-art thermoelectric nanocomposites(TENCs)have very low lattice thermal conductivity mainly due to the phonon scattering by nano-inclusions.In these TENCs,the lattice thermal conductivity is near its minimum value and further reduction is relatively difficult.Alternatively,more and more researchers are trying to enhance the power factor of the TENC,as the further improvement in thermoelectric performance is likely to come from the power factor enhancement.In this presentation,several effects to enhance the power factor will be discussed,including the quantum confinement effect,energy filtering effect and two phase inequality effect.Based on the simulation results from multiscale modeling of TENC,we will explain under which conditions such effects can be utilized and to what extent the power factor can be improved by utilizing such effects.The advantages and disadvantages of each effect will also be discussed.